(pt.ps) run
/uniterm/ProcSet findresource { def } forall

% /x is used to show incorrect input bytes.
% It only uses its argument length, not the string itself.

/glyphshow { pop } def
(T1): (xxx) x :: TEST

/glyphshow { count 1 roll } def
(T2): (xxx) x :: /.notdef /.notdef /.notdef TEST
